Treatment chambers for ligno-cellulose material and the like



Dec. 30, 1952 H. s. MESSING 2,623,820

TREATMENT CHAMBERS FOR LINGO-CELLULOSE MATERIAL AND THE LIKE Filed April 21, 1949 FIG. I.

IN VEN TOR. HJALMNL S. MESMNG m. ATTcIzN EN.

Patented Dec. 30, 1952 2,623,820 TREATMENT CHAMBERS roa mono-oer.-

LULOSE MATERIAL AND THELIKE Hialmar S. Messing, New ,York, N. Y.

Application April 21, 1949, Serial No. 88,732

Claims.

1 This invention relates to improvements in pressure vessels or reaction chambers for treating material in a closed pressure system. More especially, it relates to improvements in such vessels or reaction chambers over that disclosed in U. S. Patent 2,145,851 to Asplund covering apparatus for the production of pulp from lignocellulose materials, such as wood chips and the like.

The Asplund system involves the use of a treatment chamber in which the material to be pulped is subjected to an environment of steam or other gaseous environment chemically inert to the material, the temperature of the environment being above 212 F. and sufficiently high to markedly soften the ligneous substance of the middle lamella which binds the individual fibers together, after which. the material is mechanically refined or deiibrated while in the same environment and under the same conditions.

A primary object of the invention is the provision of a compact and eflicient treatment chamber of the character indicated which may be readily interposed as a unitary structure between the feeding means and mechanical deflbrating mechanism in an Asplund system without requiring modification of the conventional components thereof.

Another object of the inventlonis the provision of a treatment chamber comprising a plurality of series connected conduit sections defining a path of flow for the material to be treated and wherein each of the conduit sections is provided with removable conveying means for advancing the material along its pathof flow in a positive and uniform manner. Another feature of the invention resides in the novel manner of mounting the conveying means in each conduit section so that the conveying means may be readily removed and the interior of the conduit section may be easily made accessible in order to greatly facilitate periodic inspection, cleaning and repair.

An additional feature of the invention resides in a novel, simple and efiicient suspension arrangement for interconnecting and supporting the ends of the conduit sections at both ends of the treatment chamber in such a manner as to provide a chamber defining a considerably greater path of flow and having a proportion ately greater capacity than has heretofore been practicable.

The foregoing objects as well as additional feature and advantages of the invention will be readily apparent in the course of the following 2 detailed description taken in connection with the accompanying drawing which illustrates a preferred embodiment of the invention, and wherein:

Fig. 1 is an elevational view of a reaction chamber embodying the features of the invention, the chamber being shown as part of a typical 'Asplund installation including feeding means and mechanical deflbrating apparatus;

and

Fig. 2 is an enlarged fragmentary detail view illustrating a preferred manner of removably mounting the shaft of the conveying means within each of the conduit sections.

Referring now to the drawings in greater detail, the pressure vessel or reaction chamber is generally designated by reference numeral Ill and is provided with an inlet conduit Illa.- with which is associated suitable feeding means for introducing wood chips or other lingo-cellulose material into the pressure vessel. The particular feeding device designated in Fig. l. is of the rotary type and is adapted to feed material into the system in incompacted form while maintaining a seal on the pressure vessel I. Feeding means 60 includes a rotoril supported independently of housing 62 in bearings 63 for rotation within said housing and having pockets (not shown) arranged for alternately receiving material from a hopper 64 and feeding funnel 65 and to empty the material into pressure vessel It in the discharge position of the pockets. The discharge of material is facilitated by conveying steam to the bottom of the pocket in the discharge position thereof at a pressure greater than that prevailing in the pressure vessel I 0'. A blow-off conduit 66 extends from housing 62 to a steam pipe 61 disposed adjacent the top of hopper B4 in order to dissipate the pressure in the emptied pocket prior to refilling and to preheat the material being fed-,to the pressure vessel Ill. Since the 'feeding. device does not constitute the subject matter of the present invention, it will not be described here in greater detail. It will of course be understood that other types of feeding means might be employed for introducing material into pressure vessel H), such as, for example, the continuous-compression screw feed and the reciprocating, plug-forming plunger feed described in the aforementioned Asplund patent.

Pressure vessel It comprises a plurality of horizontally extending, series-connected conduit sections H, I! and I3 which define a continuous path of flow for the material through the vessel.

A single vertical passage l4 interconnects conduit sections II and I2 adjacent one end of pressure vessel It and another single vertical passage |5 interconnects conduit sections 2 and I3 adjacent -rate depending upon the desired treating time' preferably formed with interrupted flights, as

shown in Fig. 1, for thorough mixing of the material passing through the conduit sections of the pressure vessel and for repeatedly lifting and dropping portions of the material out of and 7 into the reaction mixture. a

. ment, the screw conveyors are readily removablesaid conduit sections from inlet conduit lta to discharge conduit I9. I

Intermediate conveyor ll in the middle conduit section l2 may be driven from a motor (which may be also employed for driving the rotor 8| of the feeding device) by means of a drive chain 2| engaging a sprocket 22 carried by one end of saidintermediate screw conveyor. Said screw tion l2. Screw conveyors l6 and I8 are preferably driven from intermediate screw conveyor ll by means of suitable gearing, as will appear more fully hereinbelow, and said conveyors I6 and 18 will accordingly have a direction of rotation opposite to that of said intermediate conveyor in order toconvey thematerial in the required direction through the pressure vessel, as indicated by the arrows in Fig. l.

An important feature of the invention resides in a removable mounting arrangement for screw conveyors l6, l1 and I8, as best shown in Fig. 2, which illustrates the mounting of the intermediate screw conveyor II as being typical of the mounting of the remaining screw conveyors within their respective conduit sections. Conduit section I2 is formed with an enlarged mouth portion or flange 23 defining an annular abut-.

ment or shoulder 24 adapted to retain a closure member or disc 25 having a central bearing portion 250 through which the conveyor shaft IIn extends outwardly of conduit section |2. Closure disc 25 is preferably provided with an undercut peripheral recess for steam-tight engagement against conduit shoulder 24. A packing gland 26 insures steam-tight engagement of conveyor shaft Ila.

Locking ring 21 may be threadedly engaged within conduit flange 23 for retaining closure disc '25 in operative position. Threaded plugs 28 may be provided in locking ring 21 in order to serve'as auxiliary fastening means securing closure disc 25 in position. Shaft Fla. is reduced in diameter as at 29 and retains a fixed thrust member or bearing 30 having lugs 30a for the reception of the reduced end of holding pins 3| firmly secured at their opposite ends to closure disc 25 as by welding. Adjacent thrust member 30 is disposeda gear 32 keyed to shaft Ila. Conveyors l5 and I8 are mounted in a similar manner except that the inner ends of conveyor shafts I61: and |8a may be supported within their respective conduits by suitable hangers or bearmgs (not shown). I

' Driving gear 32 meshes with driven gears 33 and 34 carried on conveyor. shafts I61: and Ila respectively so that rotation of intermediate screw conveyor II by means of drive chain 2| and sprocket 22 will be accompanied by rotation of upper and lower screw conveyors l5 and I8 respectively. Screw conveyors -|5, l8 and I! are By reason of the described mountingarrangefrom their respective conduit sections for periodic inspection, cleaning and repair purposes and having outer connecting flanges eliminated. Thrust bearings 30 prevent outward axial displacement of the screw conveyors.

A supporting member or plate 35 may be provided on the left side of the pressure vessel for interconnecting the ends of the conduit section ll, l2 and I3, said plate having openings to receive and closely fit about the outer surfaces of the mouth flanges 23 of said conduit sections. The assembly may be suspended from a fixed support '5 by means of shackle bolts 30 secured to plate 35. Another plate 31 may be provided on the right side of the pressure vessel which may rest on a support T. Auxiliary supporting plates 38 and 33 may be provided between conduit sections II and i2 in order to support the v weight of the feeding mechanism ill.

The material passes through the conduit sections of the pressure vessel to the discharge pipe I! through the bottom of which the material is fed to the defibrator unit 50 by an internal screw feed (not shown) driven by means of a sprocket.

The defibrating unit 53 comprises elements shown and described in the aforementioned Asplund patent and essentially comprises a stationary abrading disc (not shown) and a rotary feeding disc mounted on a shaft 5| journaled in bearings 52 and 53. Adjusting-mechanism 54 is provided to exert pressure on shaft 5| in order to regulate the clearance between the stationary and rotating abrading discs which mechanically separate and refine the fibers. Steam issupplied to the feeding mechanism, the pressure vessel and the defibrating unit from a steam main 4! by means of supply branches 4|, 42 and 43 respectively. 7

Since certain modifications may be made in the pressure vessel of the present inventionwithout departing from the scope thereof, it is in-' a shaft extending externally of said conduit through said apertured closure disc, locking means on said conduit for retaining said closure disc in posit-ion, an external thrust bearing supported on said shaft, members connecting said thrust bearing with said disc for preventing-outward axial displacement of said shaft.

2. A pressure vessel for treating ligno-cellulose material comprising a plurality of series-connected conduits defining a path of flow for the material to be treated, each of said conduits being open at one end, an apertured closure disc re- Y movably retained at the open end of each of said said conveying means comprising a rotary screw member having a shaft extending externally of said conduit through said apertured closure disc, locking means on each of said conduits for retaining said closure disc in position, an external thrust bearing supported on each of said shafts, members connecting aid thrust bearing with said disc for preventing outward axial displacement of said shaft.

3. A pressure vessel for treating ligno-cellulose material comprising a plurality of series-connected conduits defining a path of flow for the material to be treated, each of said conduits being open at one end and having an internal abutment shoulder adjacent said open end, an apertured closure disc removably enaageable against the internal shoulder for each of said conduits,

each of said conduits having conveying means for transporting the material therethrough, said conveying means comprising a rotary screw member having a shaft extending externally of said conduit through said apertured closure disc,'

locking means on each of said conduits for retaining said closure disc in position, an external thrust bearing supported on each of said shafts, members connecting said thrust bearing with said disc for preventing outward axial displacement of said shaft, supporting plates interconnecting the ends of said conduits on both sides of said pressure vessel.

4. In an apparatus for treating ligno-cellulose material comprisingat least three series-connected superposed conduits defining a continuous path of flow for the material to be treated. each of said conduits being open at one end, an apertured closure disc removably retained at the open end of each of said conduits, rotary means in each of said conduits for transporting material therethrough, a'shaft for each of said rotary means extending externally of said conduits and through said apertured closure discs, motor means for driving the middle one of said shafts from one end thereof, and means including bearing means on the opposite ends of said shafts and supported by said apertured closure discs for driving said transporting means in upper and lower ones of said conduits from said middle shaft.

5. In an apparatus for treating ligno-cellulose material comprising a conduit having an'inlet opening and a discharge opening and defining a path of fiow for the material to be treated, said conduit including a cylindrical body having an end encircled by a band of larger diameter than said body, said band having an internally-threaded portion disposed beyond the end of the body, an apertured disk fitted within said band and abutting against the end of the body within the band, a threaded locking ring threadably engaging the internal threads of the band and clamping the disk against the end of the body, a shaft extending externally of the: conduit through the apertured closure disk, an, external thrust bearing on the shaft externally of the conduit, said bearing having lateral ears, and pins fixed to the disk and secured in said ears.

- HJAIMAR S. MESSING.

REFERENCES crrEn The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 233,568 Southan Oct. 19, 1880 288,428 Gregory et a1 Nov. 13, 1883 536,785 Griesser Apr. 2, 1895 848,484 Newnham Mar. 26, 1907 890,112 Wheeiwright June 9, 1908 1,054,839 Hansen Mar. 4, 1913 1,375,714 McLeod Apr. 26, 1921 1,388,718 Jensen Aug. 23, 1921 1,449,280 Ginn Mar; 20, 1923 1,735,393 Hiller Nov. 12, 1929 2,145,851 Asplund Feb. 7, 1939 2,425,024 Beveridge et a1. Aug. 5, 1947 

1. A PRESSURE VESSEL FOR TREATING LIGNO-CELLULOSE MATERIAL COMPRISING A CONDUIT HAVING AN INLET OPENING AND A DISCHARGE OPENING AND DEFINING A PATH OF FLOW FOR THE MATERIAL TO BE TREATED, AN APERTURED CLOSURE DISC REMOVABLY RETAINED AT ONE END OF SAID CONDUIT FOR RETAINING SAID CLOSURE A SHAFT EXTENDING EXTERNALLY OF SAID CONDUIT THROUGH SAID APERTURED CLOSURE DISC, LOCKING MEANS ON SAID CONDUIT FOR RETAINING SAID CLOSURE DISC IN POSITION, AN EXTERNAL THRUST BEARING SUPPORTED ON SAID SHAFTS, MEMBERS CONNECTING SAID THRUST BEARING WITH SAID DISC FOR PREVENTING OUTWARD AXIAL DISPLACEMENT OF SAID SHAFT. 